A strict seven-day deadline for filing a petition challenging the result of a chief executive election is constitutional, the Court of Final Appeal ruled yesterday.

In a written judgment, the top court said the inflexible time limit was lawful as a petition was meant to be the fastest way of questioning an election.

The five-judge panel overturned a decision by Mr Justice Johnson Lam Man-hon in the Court of First Instance saying the time limit was unconstitutional if it was not up to the court's discretion to extend the deadline.

The case stemmed from an election challenge mounted by unsuccessful chief executive candidate Democrat Albert Ho Chun-yan. Ho claimed Leung Chun-ying made false or misleading statements in last year's campaign about illegal structures at his house on The Peak. Ho said it amounted to illegal conduct under the election ordinance and that Leung was unduly elected. Lam dismissed Ho's challenge, saying it had no real prospect of success - a decision that was earlier upheld by the top court.

But yesterday, despite arguments that the strict deadline denied people the right of access to the courts, the highest court ruled this right was not absolute, given the need for a speedy resolution. "The determination that seven days is the appropriate limit for the lodging of election petitions is one that does involve considerations other than legal ones," Chief Justice Geoffrey Ma Tao-li wrote in the 40-page judgment.

The court also ruled that a chief executive candidate who filed a petition could still launch a judicial review challenging the result within 30 days of the poll announcement. But the grounds must be different from those covered by the election petition provisions. The ruling overturned Lam's decision that if a candidate filed an election petition, they could not launch a judicial review. Ho's lawyers had argued the deadline may cause injustice where facts supporting a petition emerged only after seven days.